Boots of the type mentioned above are known in a variety of forms from the prior art. They are increasingly manufactured from hard polymer materials which have improved resistance in mechanical and chemical terms in comparison to previously used flexible materials. The boots have a first attachment region for attachment to a first component, in particular an outer joint member, and a second smaller attachment region for attachment to a second component, in particular in the case of a shaft, and a fold region which extends between the first attachment region and the second attachment region and has a multiplicity of annular folds or convolutes. These annular folds are embodied as external folds which each have two annular sidewall portions, connected via an annular fold peak, and are each arranged between two annular fold roots.
A problem with the use of boots, in particular for homokinetic sliding or constant velocity universal joints, are the fatigue phenomena occurring during operation when polymer materials are used. These fatigue phenomena are caused by permissible, temperature-dependent strain amplitudes being exceeded. In the case of the said joints, alternating tension/compression strains occur as a result of the alternating bending due to the folding open and folding closed of fold roots during the rotation of a bent boot.
What is needed is a boot which is of advantageous design with respect to its fatigue behavior.